Structural and catalytic roles of the human 18S rRNA methyltransferases DIMT1 in ribosome assembly and translation.

ABSTRACT: rRNA-modifying enzymes participate in ribosome assembly. However, whether the catalytic activities of these enzymes are important for the ribosome assembly and other cellular processes is not fully understood. Here, we report the crystal structure of WT human dimethyladenosine transferase 1 (DIMT1), an 18S rRNA N^6,6-dimethyladenosine (m₂^6,6A) methyltransferase, and results obtained with a catalytically inactive DIMT1 variant. We found that DIMT1^+/- heterozygous HEK 293T cells have a significantly decreased 40S fraction and reduced protein synthesis but no major changes in m₂^6,6A levels in 18S rRNA. Expression of a catalytically inactive variant, DIMT1-E85A, in WT and DIMT1^+/- cel

SUBMITTER: Shen H 

PROVIDER: S-EPMC7443495 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature